Scrolling through the MENU options will also provide access to several advanced utility functions within the NexStar such as cord wrap and anti-backlash.
Cord Wrap – Cord wrap safeguards against the telescope slewing more than 360º in azimuth and wrapping the power cord around the base of the telescope. The cord wrap menu has two settings; batteries and power cord. By default, the cord wrap feature is set to "batteries" when the telescope is powered on. If using the NexStar with a AC adapter, change the setting to "power cord", this will activate the cord wrap feature.
Anti-backlash– All mechanical gears have a certain amount of backlash or play between the gears. This play is evident by how long it takes for a star to move in the eyepiece when the hand control arrow buttons are pressed (especially when changing directions). The NexStar's anti-backlash features allows the user to compensate for backlash by inputting a value which quickly rewinds the motors just enough to eliminate the play between gears. The amount of compensation needed depends on the slewing rate selected; the slower the slewing rate the longer it will take for the star to appear to move in the eyepiece. Therefore, the anti-backlash compensation will have to be set higher. You will need to experiment with different values; a value between 20 and 50 is usually best for most visual observing, whereas a higher value may be necessary for photographic guiding.
To set the anti-backlash value, scroll down to the Azm Backlash or Alt Backlash and press ENTER. Enter a value from 0-100 for both azimuth and altitude and press ENTER after each one to save these values. NexStar will remember these values and use them each time it is turned on until they are changed.
For the best possible pointing accuracy, always center the alignment stars using the up arrow button and the right arrow button. Approaching the star from this direction when looking through the eyepiece will eliminate much of the backlash between the gears and assure the most accurate alignment possible.
Model Select – When the NexStar is first powered on, the hand control display allows you to select your NexStar from a list of different models. If for some reason the incorrect model was selected, the Model Select utility feature allows you to re-select the proper NexStar model from the displayed list. Once the correct NexStar model has been selected the power needs to be restarted before beginning the alignment procedure. NOTE: If your hand control has been pre-set at the factory, it will say NexStar Ready - Custom when first turned-on. Do not use the Model Select feature to change the model type; doing so may alter the telescope's pointing accuracy.
